Heretofore the background of the caption text in directory menus has been highlight colored to assist the operator in selecting a command entry. This background color change was typically instantaneous, a two frame transition done between frames. That is, the background changed from a non-highlight color in one frame to the highlight color in the next frame as the cursor touched the command entry. To the operator, this change to highlight color appeared instantaneous. Such abrupt changes are rare in the real world outside of the electronic world of PC display monitors. Most real world changes are smooth transitions occurring over a perceptible time period. Oncoming traffic approaches us smoothly over a ten second time frame or longer. Elevator doors open and shut in several seconds. Coffee may spill over a time period of 1/2 second. Hardly any real world events are step changes occurring faster than the reaction time of the human retina--about 1/20 of a second. However, abrupt changes are commonplace in the electronic world. A person interfacing with at a PC may be exposed to hundreds of instantaneous changes in only a few minutes. Over time these repeated visual impacts can cause operator tension, headaches and other deleterious effects. The operator distress caused by visual impacts may be viewed as carpal tunnel syndrome of the optic nervous system, and is an affront to the new workplace science of ergonomics.